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Corridors are intended to increase species survival by abating landscape fragmentation resulting from the conversion of natural habitats into human‐dominated matrices. Conservation scientists often rely on 1 type of corridor model, typically the least‐cost model or current‐flow model, to construct a linkage design, and their choice is not usually based on theory or empirical evidence. We developed a method to empirically confirm whether corridors produced by these 2 models are used by target species under current landscape conditions. We applied this method in the Gamba landscape between 2 national parks in southwestern Gabon. We collected signs of presence of African forest elephant (Loxodonta cyclotis), forest buffalo (Syncerus caffer nanus), and 2 apes, western lowland gorilla (Gorilla gorilla gorilla) and central chimpanzee (Pan troglodytes troglodytes), on transects. We used patch‐occupancy models to identify least‐cost and current‐flow corridors for these 4 species. On average, 28.7% of current‐flow corridors overlapped with least‐cost corridors, confirming that the choice of corridor model can affect the location of the resulting linkage design. We validated these corridors by monitoring signs and examining camera detections on new transects within and outside modeled corridors. Current‐flow corridors performed better than least‐cost corridors for elephants, whereas the opposite was found for buffalo and apes. Locations of the highest priority corridors for the 3 taxa did not overlap, and only 18.3% of their combined surface was common among 2 species. We used centrality metrics to calculate the average contribution of corridor pixels to landscape connectivity and derived an index that can be used to prioritize corridors. As a result, we recommend protecting at least 17.4% of the land surface area around Gamba town to preserve the preferred travel routes of the target species. Article impact statement: Choice of corridor model affects corridor locations and needs empirical validation before linkage design is approved. [ABSTRACT FROM AUTHOR]

Experimental studies in laboratory settings have demonstrated a critical role of parasite interactions in shaping parasite communities. The sum of these interactions can produce diverse effects on individual hosts as well as influence disease emergence and persistence at the population level., A predictive framework for the effects of parasite interactions in the wild remains elusive, largely because of limited longitudinal or experimental data on parasite communities of free-ranging hosts., This 4-year study followed a community of haemoparasites in free-ranging African buffalo ( Syncerus caffer). We detected infection by 11 haemoparasite species using PCR-based diagnostic techniques, and analyzed drivers of infection patterns using generalized linear mixed models to understand the role of host characteristics and season on infection likelihood. We tested for (i) effects of co-infection by other haemoparasites (within guild) and (ii) effects of parasites infecting different tissue types (across guild)., We found that within guild co-infections were the strongest predictors of haemoparasite infections in the buffalo; but that seasonal and host characteristics also had important effects. In contrast, the evidence for across-guild effects of parasites utilizing different tissue on haemoparasite infection was weak., These results provide a nuanced view of the role of co-infections in determining haemoparasite infection patterns in free living mammalian hosts. Our findings suggest a role for interactions among parasites infecting a single tissue type in determining infection patterns. [ABSTRACT FROM AUTHOR]

Sarcocystis infections have been reported from the African buffalo ( Syncerus caffer), but the species have not been named. Here we propose a new name Sarcocystis cafferi from the African buffalo. Histological examination of heart (92), skeletal muscle (36), and tongue (2) sections from 94 buffalos from the Greater Kruger National Park, South Africa, and a review of the literature revealed only 1 species of Sarcocystis in the African buffalo. Macrocysts were up to 12 mm long and 6 mm wide and were located in the neck muscles and overlying connective tissue. They were pale yellow; shaped like a lychee fruit stone or cashew nut; turgid or flaccid and oval to round (not fusiform). By light microscopy (LM) the sarcocyst wall was relatively thin. By scanning electron microscopy (SEM), the sarcocyst wall had a mesh-like structure with irregularly shaped villar protrusions (vp) that were of different sizes and folded over the sarcocyst wall. The entire surfaces of vp were covered with papillomatous structures. By transmission electron microscopy (TEM), the sarcocyst wall was up to 3.6 μm thick and had highly branched villar protrusions that were up to 3 μm long. The villar projections contained filamentous tubular structures, most of which were parallel to the long axis of the projections, but some tubules criss-crossed, especially at the base. Granules were absent from these tubules. Longitudinally cut bradyzoites were 12.1 × 2.7 μm in size, had a long convoluted mitochondrion, and only 2 rhoptries. Phylogenetic analysis of 18S rRNA and cytochrome C oxidase subunit 1 (cox1) gene sequences indicated that this Sarcocystis species is very closely related to, but distinct from, Sarcocystis fusiformis and Sarcocystis hirsuta. Thus, morphological findings by LM, SEM, and TEM together with molecular phylogenetic data (from 18S rRNA and cox1) confirm that the Sarcocystis species in the African buffalo is distinct from S. fusiformis and has therefore been named Sarcocystis cafferi. [ABSTRACT FROM AUTHOR]

Background: It has been established that mammalian egg zona pellucida (ZP) glycoproteins are responsible for species-restricted binding of sperm to unfertilized eggs, inducing the sperm acrosome reaction, and preventing polyspermy. In mammals, ZP apparently represents a barrier to heterospecific fertilization and thus probably contributes to reproductive isolation between species. The evolutionary relationships between some members of the tribe Bovini are complex and highly debatable, particularly, those involving Bos and Bison species for which interspecific hybridization is extensively documented. Because reproductive isolation is known to be a major precursor of species divergence, testing evolutionary patterns of ZP glycoproteins may shed some light into the speciation process of these species. To this end, we have examined intraspecific and interspecific genetic variation of two ZP genes (Zp2 and Zp3) for seven representative species (111 individuals) from the Bovini tribe, including five species from Bos and Bison, and two species each from genera Bubalus and Syncerus. Results: A pattern of low levels of intraspecific polymorphism and interspecific divergence was detected for the two sequenced fragments each for Zp2 and Zp3. At intraspecific level, none of neutrality tests detected deviations from neutral equilibrium expectations for the two genes. Several haplotypes in both genes were shared by multiple species from Bos and Bison. Conclusions: Here we argue that neither ancestral polymorphism nor introgressive hybridization alone can fully account for haplotype sharing among species from Bos and Bison, and that both scenarios have contributed to such a pattern of haplotype sharing observed here. Additionally, codon-based tests revealed strong evidence for purifying selection in the Zp3 coding haplotype sequences and weak evidence for purifying selection in the Zp2 coding haplotype sequences. Contrary to a general genetic pattern that genes or genomic regions contributing to reproductive isolation between species often evolve rapidly and show little or no gene flow between species, these results demonstrate that, particularly, those sequenced exons of the Zp2 and the Zp3 did not show any contribution to reproductive isolation between the bovine species studied here. [ABSTRACT FROM AUTHOR]

Many animals aggregate into organized temporary or stable groups under the influence of biotic and abiotic factors, and some studies have shown the influence of habitat features on animal aggregation. This study, conducted from 2002 to 2004 in the Dzanga-Ndoki National Park, Central African Republic, studied a herd of forest buffaloes ( Syncerus caffer nanus) to determine whether spatial aggregation patterns varied by season and habitat. Our results show that both habitat structure and season influenced spatial aggregation patterns. In particular, in open habitats such as clearings, the group covered a larger area when resting and was more rounded in shape compared to group properties noted in forest during the wet season. Moreover, forest buffaloes had a more aggregated spatial distribution when resting in clearings than when in the forest, and individual positions within the herd in the clearing habitat varied with age and sex. In the clearings, the adult male ( n = 24) was generally, on most occasions, located in the centre of the herd ( n = 20), and he was observed at the border only four times. In contrast, females ( n = 80) occupied intermediate ( n = 57), peripheral ( n = 14) and central positions ( n = 9) within the group. Juveniles ( n = 77) also occurred in intermediate ( n = 64) and peripheral positions ( n = 13). Based on these results, we concluded that habitat characteristics and social behaviour can have relevant effects on the spatial distribution of animals within a group. [ABSTRACT FROM AUTHOR]

The succulent thicket of the Eastern Cape, South Africa, is characterized by densely wooded vegetation that is dominated by succulents with little understory of ephemeral and weakly perennial grasses and forbs. Studies have developed around the question: how do bulk grazers such as the African buffalo ( Syncerus caffer) survive in the succulent thicket? In this study, the diet of the African buffalo at the Great Fish River Reserve (GFRR) was studied in two seasons (wet and dry). The diet profile was assessed from faecal matter, using the micro-histological analysis method. During the wet season, grass species contributed 72% to the diet while 28% was contributed by browse species. In the dry season there was a significant increase in the intake of browse by 5% (χ2 = 19.94, df = 11, P < 0.05). There were species that were neglected in the wet season but became principal dietary items in the dry season, these included Setaria neglecta, Cymbopogon plurinodis, Capparis sepiaria and Portulacaria afra. Diet quality, as estimated from faecal samples, suggested that the buffalo were nutritionally stable; however, the presence of sarcoptic mange in the buffalo suggests nutritional stress. [ABSTRACT FROM AUTHOR]

Africanastrongylus giganticus n. sp. is described based on large ostertagiine nematodes occurring in the abomasum of African buffalo, Syncerus caffer, from Uganda; this represents the second species recognized in the genus. Specimens of A. giganticus are characterized by large size (15-19 mm in total length), a strongly tapering synlophe in the cervical region, and a great number of ridges at all levels of the body (maximum 72 attained in the third quarter); numbers of ridges exceed that reported among any known genera and species of the Ostertagiinae. We refer A. giganticus to this genus based on a strongly tapering lateral synlophe, relatively large numbers of ridges at all levels of the body, miniscule cervical papillae, poorly demarcated divisions of the ovejector, absence of vulval cuticular inflations, and the presence of slightly protruding lips at the vulva. It is distinguished from its congener, Africanastrongylus buceros, in total length, maximum number of ridges (68-72 vs. 53, respectively), structure and disposition of the synlophe, presence of strongly spiraled ovarian tracks, and eggs that are distributed in 3 or more rows in the uterus. A superficial resemblance to Longistrongylus meyeri, the only other large ostertagiine in the African fauna, is evident; these species, however, are distinct based on the synlophe and other characters. Recognition of a second species of Africanastrongylus represented by nematodes of large size suggests that prior reports of L. meyeri in Syncerus caffer may be attributable to A. giganticus. [ABSTRACT FROM AUTHOR]

Evaluating animal body condition is a necessary component of many ecological studies. Although many methods for assessing animal body condition have been developed, relatively few can be used for estimating condition on live animals. Noninvasive body condition scoring techniques have been developed for assessing condition in livestock and more recently such techniques have been applied to wild ungulates. In this study, we examined the reliability of a body condition scoring technique for assessing condition in African buffalo ( Syncerus caffer caffer). We compared a body condition score (BCS) based on visual assessment and manual palpation of an animal’s body to two standard metrics of condition widely used in mammals: kidney fat index (KFI) and haematocrit (HCT). Across all buffalo, BCS was significantly and positively correlated with both KFI and HCT. For HCT, this pattern was observed among adults, juveniles, males and females; and in the wet season but not in the dry season. For KFI, BCS was significantly and positively correlated with KFI among adults, juveniles and males, but not in females. Overall, our results suggest that the BCS technique can serve as a useful method for estimating body condition in buffalo. [ABSTRACT FROM AUTHOR]

Documenting within species group size variation is important to completely understand social organization within species and to interpret variation among species. Here, I investigated group size of African buffalo Syncerus caffer over 2 years in a heterogeneous landscape. African buffalo use closed continuous forest and vast open savannas, and anecdotal observations suggest that habitat type influences their social structure. While the Cape buffalo Syncerus caffer caffer is well studied, few data exist for the forest-dwelling Syncerus caffer nanus. I observed forest buffalo at Lopé National Park, Gabon, and examined variation of group size. Eighteen forest buffalo herds used the study area with an estimated population of 342 individuals (∼5 buffalo km−2). The mean group size for the 18 herds was 12 ± 2 (range of means=3–24), considerably smaller than Cape buffalo herds. For eight radiocollared forest buffalo, the mean group size was stable, varying little with time of day, across seasons, or between savanna and marsh habitat. However, herd size varied widely across herds, from fewer than 10 individuals in the smallest herds to more than 20 buffalo in the largest. Large herd size is associated with home ranges that contain substantial areas of open habitat, and thus more food resources than forested habitats. [ABSTRACT FROM AUTHOR]

The evolution and maintenance of elaborate secondary sexual characters in males have been the subject of intense interest since Darwin''s time. Parasite-mediated sexual selection (PMSS) suggests that elaborate ornaments serve as honest indicators of male health and parasite resistance. Studies testing this key prediction of PMSS have largely focused on ornaments, with the role parasites might play in the maintenance of elaborate weapons being relatively understudied. Here, we tested whether weapon (horn) size was an indicator of health status in male and female African buffalo, Syncerus caffer. We examined whether individuals with larger horns were less likely to be infected with parasites, and had lower parasite loads and stronger immune systems. In males, horn size was significantly negatively correlated with the number of different parasites infecting an individual (parasite richness), the likelihood of infection with strongyle nematodes and coccidia, and strongyle intensity. In females, horn size was significantly negatively correlated with parasite richness, occurrence of coccidia infection, coccidia intensity and white blood cell count. These findings were robust when the effects of body condition, age and season were controlled for, consistent with the idea that horns function as honest indicators of health in both sexes. Our study provides new insight into the evolution and maintenance of elaborate weapons in mammals, suggesting a role for PMSS in both males and females. [Copyright &y& Elsevier]

The forest buffalo (Syncerus caffer nanus) typically inhabits the dense rain forests of western and central Africa. We recorded the 1st data on the behavior and social interactions of forest buffalo in natural forest clearings that represent crucial places in the rain forest for feeding and social interactions among individuals. Data were collected from a buffalo herd during January 2002-January 2004 in the Bai-Hokou study area (Dzanga-Ndoki National Park, Central African Republic). We analyzed typical behaviors (i.e., grazing, resting or ruminating, and moving) of both the herd and individuals (from 16 to 24 buffalos), as well as the most frequent social interactions. Spatial distribution among buffalos in the herd, related to both distance from forest edge and to the season (wet versus dry seasons), showed that the adult male was commonly closer to the females than to juveniles. Individuals were generally further away from each other when in the vicinity of the forest edge. Moreover, at greater distances from the forest edge, the number of buffalos in the herd increased. During the wet season, the herd was generally smaller and individuals were more spread out within the same clearing. The most common behavior of the male, females, and juveniles was resting or ruminating. Behavioral interactions by adults were mainly addressed to juveniles. [ABSTRACT FROM AUTHOR]

The forest buffalo Syncerus caffer nanus is one of the three subspecies of African buffalo inhabiting the rainforests of Western and Central Africa. Because of its secretive behaviour and main habitat (dense rainforests), there is little quantitative information on the habitat preferences of this buffalo. We present here the first data on the frequencies of this species along a habitat gradient ranging from clearings and rivers to forests, as well as the characteristics of the buffalo's resting places. We recorded information from a buffalo herd during the period January 2002–January 2004 in the Bai-Hokou area (Dzanga-Ndoki National Park, Central African Republic). Resting places were firstly compared with available habitat (i.e. resting vs. random sites) and, successively, comparisons were made between diurnal versus nocturnal and wet versus dry season resting places. Forest buffalos were found to be highly dependent on clearings, as well as on the more open forest stands, characterized by large trees and open canopy. Such preferences could be due to the tendency of the buffalos to rest all together; open patches are likely to facilitate social interactions between the members of the herd. [ABSTRACT FROM AUTHOR]

Patterns of association in many ungulate species vary throughout the year, with males periodically segregating from females. Sexual segregation can occur if males and females use different habitats (habitat segregation), occupy exclusive ranges (spatial segregation) or occur in separate social groups (social segregation). Previous studies on social segregation in ungulates have focused mostly on non-reproductive periods and species in temperate systems with short mating seasons. This study examined social segregation in African buffalo Syncerus caffer at Hluhluwe-iMfolozi Park, South Africa, during their 6-month mating season. During this period, mature male buffalo alternated between joining mixed-sex herds which comprise females and young, and small all-male groups. Activity patterns of male buffalo in both group types were examined to determine if differences in time allocation or activity asynchrony could explain the observed segregation. Mature males foraged for less time than both adult females and younger males when they were with mixed herds. Mature male buffalo differed in how their active time was apportioned to foraging and reproductive activities between the two group types. Females maintained group cohesion despite only low synchrony in activity, therefore segregation of male buffalo could not be explained by the activity budget hypothesis. For males in mixed-sex herds, reproductive activities were apparently at the expense of foraging time. The high time and energy costs of reproductive activities were probably responsible for the periodic separation of male buffalo from mixed herds during the extended mating period. [ABSTRACT FROM AUTHOR]

We examined the importance of browse and grazing in the diet of 28 African buffalo Syncerus caffer from Chobe National Park, Botswana, through analysis of stable isotope ratios of tooth collagen. Carbon isotope levels indicated that the assimilated diet was wholly dominated by grasses. Variations in nitrogen isotope values were consistent with variation in individual δ13C values being due to variations in the small proportion of non-grasses in the diet. There were no significant sex differences in diet. [ABSTRACT FROM AUTHOR]

Unique features of giraffe Giraffa camelopardalis anatomy are its long neck and slender long limbs. Its neck vertebrae should be light and have low density to make it manoeuvrable while the limb bones should have high density to provide the strength to support the giraffe's mass. Giraffes also have a very high vertical growth rate, a diet with a high Ca:P ratio, and a skeleton that constitutes a high proportion of its body mass. To investigate whether the giraffe skeleton is affected by its anatomy and biology, giraffe bone density and morphology were compared with those of African buffalo Syncerus caffer, an artiodactyl of similar mass, more conventional anatomy, a lower vertical growth rate, and different diet. Our results show that except for minor differences the density of giraffe bones is the same as that of buffaloes. Giraffe limb bones have a slightly greater diameter and much thicker walls than equivalent bones in buffaloes. Giraffe cervical vertebrae, unlike those in buffaloes, decrease in mass with cranial distance. We conclude that giraffe biology and anatomy do not affect bone deposition or density. However, other characteristics of their skeletons seem to be adaptations to their unique anatomy. [ABSTRACT FROM AUTHOR]

Forage selection by buffalo and the contribution of grass species to buffalo diet were investigated by comparing two herds occupying granite and basalt landscapes in the Kruger National Park. Observations spanned the late dry season, from July to October 2002. Grass remained greener in bottomlands than in midslopes or uplands within each landscape, but greenness was not significantly different between the basalt and granite landscapes. The favoured grass species remaining highly acceptable to buffalo throughout the late dry season included Panicum maximum, Panicum coloratum, Cenchrus ciliarisand Heteropogon contortus. However, the dietary contribution by these species declined with the progress of the dry season owing to a reduction in the available forage that they retained. The acceptance frequency as well as the dietary contribution of Urochloa mosambicensis, Digitaria eriantha and Eragrostis superba increased over time, while Bothriochloa spp. became moderately acceptable at the end of the dry season in October. Themeda triandra, a species highly rated as forage for cattle, appeared intermediate in its acceptability to buffalo and made a relatively small dietary contribution in both landscapes. In accordance with foraging theory, buffalo expanded the range of grass species accepted, changed the proportions of grass species in their diet and shifted their grazing locations within the landscape. [ABSTRACT FROM AUTHOR]

African buffalo (Syncerus caffer) bulls alternate between living within large mixed-sex herds, and living solitarily, or in small single-sex groups, as 'bachelors'. Using radio-telemetry, we show that bulls in northern Chobe National Park, Botswana, spend the early dry season as bachelors, but switch to herd attendance in the later dry season. Bulls may move between different mixed herds at this time, but are very rarely found as bachelors. As bachelors they are found more often in Baikaieawoodland, away from the floodplain grassland and adjacent habitats, than are herds during the same period. This pattern of herd affiliation differs from that found in studies elsewhere in Africa. It seems most likely that it results from a combination of seasonal mating opportunities; foraging preferences and seasonal forage availability; and predation avoidance, in turn determined largely by the highly seasonal, semi-arid climate. [ABSTRACT FROM AUTHOR]

Many species exhibit skewed sex ratios at birth. Here we investigate the relationships between environmental and maternal variables (as surrogates for maternal condition) and foetal sex in African buffalo Syncerus caffer and elephant Loxodonta africana of the Kruger National Park, South Africa. Using logistic regression no significant effect was found of year, maternal lactational status, maternal age, rainfall or density on foetal sex ratio. Using a subset of our data, it was also concluded that maternal body condition did not affect foetal sex ratio in buffalo. Our analyses failed to support hypotheses predicting that mothers will skew the sex ratios of their offspring in relation to their body condition. In this study, buffalo and elephant produced offspring with a sex ratio close to parity. Our results are discussed in light of the implications for testing such hypotheses in analyses of population level. [ABSTRACT FROM AUTHOR]

The 1.709 or satellite IV repeated DNA family originally isolated from the domestic cow was analyzed using Southern blotting, pulsed field gel electrophoresis, fluorescence in situ hybridization, and DNA sequencing in species belonging to the genera Bos, Bison, Bubalus, Syncerus, Boselaphus, and Tragelaphus. Hybridization indicates that the family has been amplified in Bos, Bison, Bubalus, and Syncerus but not in Boselaphus or Tragelaphus. Pericentromeric, higher-order repeat substructure exists in all species, with multimeric arrays ranging in size from 10 to 1500 kb. Sequence analysis of a 492-bp PCR product revealed comparable levels (0.2–4.5%) of intra- and interspecific divergence when species of Bos and Bison were compared, supporting the idea that species of these two genera should be recognized under the genus Bos. Alternatively, all Syncerus sequences cluster as a monophyletic group on an evolutionary tree and differ from those of Bos/Bison by about 13%. Comparing these findings with the fossil record indicates that concerted evolution has occurred since Bos/Bison and Syncerus last shared a common ancestor (5.0 MYA) but before the radiation of the genus Bos (2.5 MYA): GenBank accession numbers AY517856-AY517904. [ABSTRACT FROM AUTHOR]

During the study of the Quaternary Maghrebian bovines in 1985, the review of the Bovini (aurochs and buffalos) found in Upper Pleistocene sites of Algeria showed that in comparison with most of the African bovine assemblage the attribution of genus Pelorovis to the species antiquus was inappropriate. The biometric and cladistic data revealed a close kinship with genus Syncerus. Later, other authors’conclusions confirmed its relevance. The antique buffalo of the Aterian site of the Phacochoeri has all the characteristics of genus Syncerus, but is different in that it shows a certain number of specific characteristics described in this article. [ABSTRACT FROM AUTHOR]

The article cites a research study conducted to understand the phenomenon of herd-switching among adult female African forest buffalo, Syncerus caffer nanus, a savanna- dwelling sub-species. It is reported that buffalo herds were traditionally considered stable with little interherd movement among buffaloes. However, recent research indicates that herd-switching among these buffaloes is more common than previously reported. As a part of the study, eight adult female forest buffalo, representing eight different groups, were fitted with radio collars in December 2002. From December 2002 through December 2004, these buffaloes were tracked about twice per week. It was found that one radio-collared buffalo switched herds.